In recent years, the effects of neighborhood characteristics on children's well-being has become a topic of considerable debate in academic and policy communities and in the general public. Social, psychological and economic theory and qualitative studies suggest that many aspects of neighborhood effects and a substantial amount of research in the past few years on neighborhood effects, most studies have failed to produce persuasive and consistent results about the nature and size of these effects on children. In this projects, we propose to investigate the effects of neighborhood environments on children using an innovative new longitudinal data set (the Los Angeles family and Neighborhood Survey) and multilevel statistical models which are better suited to capture neighborhood and family effects. Our specific aims are: (1) to determine how adults and children define their own neighborhoods and how salient these neighborhoods are to daily life; (2) to examine the effects of neighborhood composition on social environmental mechanisms that are hypothesized to affect children's outcomes directly (e.g., social organization and normative climate); and (3) to assess the effects of neighborhood and family environments on children's development (specifically, achievement in reading and math and behavior problems). The proposed analysis will significantly expand our knowledge of the effects of neighborhood environments on children.